The present invention relates to an HVAC system, and more particularly to a service and diagnostic tool, which communicates with the entire HVAC system from a multiple of locations.
A heating, ventilating, and air conditioning (HVAC) system includes multiple components that function together in a coordinated manner. Typically, an HVAC system includes an indoor unit such as a gas furnace or fan coil, an outdoor unit such as an A/C or heat pump, and a thermostat. More sophisticated systems might include a multi-zone control capacity with zone control and zone dampers. HVAC systems also frequently include subsystems such as filters, humidifiers, and ventilators.
In conventional residential HVAC systems, minimal information, if any, is provided to the service technician regarding the configuration, operating status, or fault history of the HVAC system. Some of the more advanced components such as variable speed furnaces display fault codes on the individual component equipment display. Some more recent HVAC components also provide the capability for a technician to access more detailed information regarding the component status by connecting a diagnostic tool such as a laptop computer directly thereto. This, of course, requires the technician to transport the service tool to each job site. Also, the information provided by such conventional art components is limited to the single component to which the diagnostic unit is connected and not the entire system.
The technician often must operate the system in its various modes to properly assess system performance and to diagnose any problems. In conventional systems, exercise of this system is accomplished at the thermostat by setting a high heating set point to turn on the furnace or a low cooling set point to turn on the air conditioner. There is no conventional way to directly command a specific stage of heating or cooling, and, in many cases, a technician must wait for the various protection and staging timers to time out before the desired operating mode is activated.
Although effective, conventional service techniques may make the task of the service technician more difficult and time consuming, which may lead to improper installation or incorrect diagnosis. As HVAC systems continue to become more sophisticated, a higher level of training and expertise on the part of the technicians is also required.
Accordingly, it is desirable to provide a diagnostic system within an HVAC system that provides system wide diagnosis and control from a multiple of locations within the HVAC system.